Stay at Home, Protect the NHS, Save Lives

Stay at Home

The Challenge

With the emergence of COVID-19 in Wales came uncertainty for every aspect of society. Questions quickly surfaced; how and where the virus was spreading? What effect would it have on public health? How would our health and care services handle the additional pressures? And what long-term impacts would the pandemic have on health and our way of life?

Population Data Science at Swansea University Medical School turned to its world-leading, dedicated team of data scientists and analysts, who accepted the challenge to help tackle these burning questions. In recognising the scale of the task at hand, its was crucial to establish a wider, collaborative ‘task force’. And so, the One Wales approach to COVID-19 was formed.

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Quickly, a team was assembled that would draw on the necessary expertise to guide national and regional policy decision making. The team consists of leading expertise from Swansea University, HDR UKADR WalesSAIL DatabankADPBREATHE, Welsh Government, Public Health Wales and NHS Wales Informatics Service (NWIS). This has resulted in an agile and responsive approach to tackling data analysis and intelligence generation based on both the constant and newly developing priorities for tackling COVID-19 in Wales.

With access to billions of anonymised person-based records held in Population Data Science’s SAIL Databank (Secure Anonymised Information Linkage), the One Wales team were able to monitor the impact of a wide range of exposures and outcomes on the entire population using robustly de-identified data.

Over the period of the COVID-19 pandemic, it was possible to track the development of health conditions in individuals and nested within households and school populations, monitor the development and spread of the disease, evaluate the impact of exposures and the efficacy of treatments.


The intelligence generated by Population Data Science has been sought by the Welsh Government’s TAG (Tactical Advisory Group) which subsequently feeds into the UK’s SAGE (Scientific Advisory Group for Emergencies).

In their latest contribution, real-time analysis performed by Dr Fry and his team at Population Data Science, illustrates the spread of COVID-19 across Wales via an animated map. The project uses pathology data, which confirms a COVID-19 positive result based on testing and the date the test was taken. The data is held anonymously and securely in and extracted from SAIL Databank. A secure gateway, provided by SAIL, governs access to the data whilst protecting privacy. Data extracted from SAIL is then processed to generate suitable inputs for geospatial modelling.

These insights, delivered to Welsh TAG and UK SAGE, have added to our understanding of COVID-19 and have helped to shape decisions on lockdown guidance and policies in Wales.